Investigators are looking into an apartment building fire on Chicago's Southwest Side.

According to a source at the scene, there was a strong smell of gasoline inside and outside the building near Western and 35th Street in the city's Brighton Park neighborhood. Fortunately, the building was not occupied at the time.

The fire broke out around 11 p.m. Tuesday at the two-and-a-half story building.

Smoke was pouring out of the roof and firefighters worked well into Wednesday morning, trying to put out the blaze.

At one point, crews were inside the building removing paneling from the roof. The source noted that the building may have undergone some recent renovations.